Liver Anatomy

Front 1

Development

Back 1

A) The liver and biliary tree develops as a
B) hollow endodermal bud, the hepatic diverticulum, from the
C) distal foregut in the
D) 3-week embryo. The rapidly proliferating cells of the
bud penetrate the septum transversum and eventually develop into the liver, while the connection between the hepatic diverticulum and the foregut is preserved to form the bile duct. A ventral outgrowth of the bile duct gives rise to the gallbladder and cystic duct. With the rotation of the gut, the opening from the bile duct into the intestine migrates to a posterior position and the common bile duct comes to lie behind the duodenum and pancreas.

Front 2

The external appearance of the mature liver shows its division into

Back 2

A) two lobes by the umbilical fissure and falciform ligament. Further subdivisions are made on other superficial features.

Front 3

The quadrate lobe is a

Back 3

1) subdivision of the right lobe and lies to the
2) left of the gallbladder fossa and to the
3) right of the umbilical fissure.
4) The transverse hilar fissure forms the posterior boundary of the quadrate lobe and divides it from the caudate lobe posteriorly (Fig. 1).

Front 4

The internal architecture of the liver bears only a superficial relation to its external appearance. Cast studies of the biliary tree and portal venous radicles show that the

Back 4

1) liver is divided into right and left halves, according to the territories of drainage of the right and left hepatic ducts and the
2) areas of supply of the right and left branches of the portal vein and hepatic artery. This principal division is called
3) Cantlie's line, after its first description in 1898, but it is not readily visible on external examination. It runs from the
4) medial edge of the gallbladder fossa to the
5) inferior vena cava posteriorly. The nomenclature of hepatic anatomy has become
6) confused by the use of the term ‘lobe', which has been applied to both the division of the liver by its external features and the territories of drainage of the right and left hepatic ducts.

Front 5

Glisson's capsule, a peritoneal and fibrous covering, invests the liver.

Back 5

1) The reflections of the capsule on to the right hemidiaphragm form the
2) coronary ligament and
3) right triangular ligament, and the reflection from the left liver on to the left hemidiaphragm forms the left triangular ligament. Glisson's capsule is also reflected over the
4) falciform ligament. The structures at the hilum of the liver are invested in dense fibrous tissue continuous with Glisson's capsule; here this covering is known as the hilar plate. The hilar plate is continuous with the peritoneal layers investing the common hepatic and common bile duct, cystic duct, and gallbladder.

Front 6

The liver is supplied by blood

Back 6

1) 80 per cent of which comes via the portal vein and
2) 20 per cent via the hepatic artery.
3) Venous drainage is by three, large, short, hepatic veins that pass posteriorly to the inferior vena cava, which lies on the posterior surface of the liver.
4) Drainage of bile occurs from the left and right hepatic ducts to the common hepatic and bile duct, and then to the second part of the duodenum.

Front 7

The portal vein is formed by the

Back 7

1) confluence of the superior mesenteric vein and the splenic vein in front of the inferior vena cava and behind the neck of the pancreas. The portal vein
2) runs behind the pancreas to the free border of the lesser omentum, where it
3) traverses to the hilum of the liver in the hepatoduodenal ligament
4) behind the common bile duct and
5) to the right of the hepatic artery. At the hilum of the liver, the portal vein divides into left and right branches. The vein, with its accompanying branches of the biliary tree and hepatic artery, is invested in a fibrous sheath continuous with the hilarplate.

Front 8

The common hepatic artery usually arises from the

Back 8

1) coeliac axis and travels across the posterior abdominal wall to
2) lie just above the pylorus. Here it gives off the
3) gastroduodenal artery before
4) continuing as the hepatic artery proper, which then runs in the gastroduodenal ligament medial to the common bile duct and anterior to the portal vein to the hilum of the liver.
5) The hepatic artery divides into the left and right hepatic artery well below the hilum of the liver.
6) Sixteen per cent of individuals have an
7) aberrant right hepatic artery arising from the
8) superior mesenteric artery that runs in the groove to the right of the portal vein and common bile duct.
9) Less commonly, the arterial supply to the left half of the liver comes from the left gastric artery.

Front 9

The venous radicles in the liver give rise to

Back 9

1) three hepatic veins, the right, middle, and left, which are short and large. The
2) middle hepatic vein usually joins the left hepatic vein before entering the inferior vena cava. In addition, a number of
3) unnamed short veins enter the inferior vena cava directly.
4) These arise in the caudate lobe, which, because of its embryological development form the dorsal mesogastrium, has a different venous drainage

Front 10

The three hepatic veins divide the liver into

Back 10

1) four sectors, each of which is
2) further subdivided into two segments. The whole liver is therefore divisible into
3) eight segments:
4) four are in the right half, and
5) three in the left half (Fig. 2).
6) The remaining segment is the caudate lobe, which should be considered separately because of its different embryological origin, variable blood supply, and venous drainage.
7) Two differing descriptions of the segmentation of the liver are in common use, that of
8) Couinaud and that of
9) Goldsmith and Woodburne. These differ mainly in nomenclature, and the description of Couinaud will be used here.

Front 11

‘left hepatectomy

Back 11

Removal of segments II to IV

Front 12

right hepatectomy

Back 12

removal of segments V to VIII

Front 13

Each segment is supplied by

Back 13

a named portal venous radicle and is
2) drained by a segmental bile duct,
3) forming the smallest anatomical unit of hepatic resection.

Front 14

extended right hepatectomy

Back 14

Removal of segment IV (the quadrate lobe) in addition to right hepatectomy

Front 15

The intrahepatic bile ducts
right

Back 15

ducts from segments VI and VII join to form the
3) right posterior sectoral duct, which
(a) runs horizontally across the gallbladder fossa, where it is
(b) surgically accessible after localization by
(c) needle puncture or intraoperative ultrasonography.
1) The right anterior sectoral duct
(a) runs more vertically and is formed by the
(b) confluence of the ducts from segments V and VIII.

Front 16

left hepatic duct

Back 16

Segmental ducts from segments II, III, and IV merge to form the left hepatic duct
2) The duct from segment III is surgically accessible by
3) dissection in the groove to the left of the umbilical ligament, where it
4) lies anterior to its accompanying branch of the portal vein and hepatic artery.
5) The left hepatic duct runs from the base of the umbilical fissure to the hilum in the transverse hilar fissure, invested by the fibrous tissue of the hilar plate with the left portal vein lying posterior and the left hepatic artery lying inferior.
6) The left duct is surgically accessible by division of the peritoneal fold under the quadrate lobe (segment IV), a procedure known as lowering the hilar plate.

Front 17

normal' pattern is seen in.............. per cent of individuals

Back 17

less than 60

Front 18

duct of Luschka

Back 18

7) anomalous subvesical duct, the duct of Luschka, which runs in the gallbladder fossa. It is found in
8) 12 to 50 per cent of individuals, drains a variable portion of the right liver, and is potentially vulnerable during cholecystectomy.

Front 19

The gallbladder

Back 19

pear-shaped reservoir
5 to 12 cm in length
lies in a fossa on the lower surface of the liver

Front 20

D) Four parts of the gallbladder are described:

Back 20

1) the fundus,
2) the body,
3) the infundibulum, and
4) the neck.

Front 21

Hartmann's pouch

Back 21

1) pathological feature in the neck and infundibulum of the gallbladder

in the presence of gallstones.

Front 22

sphincter of Lutkens

Back 22

The wall of the cystic duct contains muscle fibres

Front 23

valve of Heister

Back 23

mucosa of the cystic duct forms crescentic folds

Front 24

Calot's triangle

Back 24

common hepatic duct to the left
cystic duct below
inferior surface of the liver

Front 25

cystic artery

Back 25

arises from the
1) right hepatic artery behind the common hepatic duct and
2) runs behind the right hepatic duct and through Calot's triangle to the gallbladder.
3) In 20 per cent of individuals the cystic artery
4) arises from a right hepatic artery that
5) runs anterior to the common hepatic duct, and the
6) right hepatic artery forms a loop or ‘caterpillar hump' with the
7) cystic artery originating from the apex in 7 per cent of individuals. In the latter case, the
8) right hepatic artery may be mistaken for the cystic artery during cholecystectomy.
9) In 10 per cent of individuals the cystic artery
10) arises proximally from the right hepatic artery and
11) runs anterior to the common hepatic duct, while the
12) right hepatic artery runs posterior to this duct.

Front 26

veins draining

Back 26

1) all arteries are normally
2) accompanied by a small vein or
3) venous plexus.
4) Some veins drain directly from the gallbladder into the liver.

Front 27

Lymphatic drainage

Back 27

1) cystic lymph node, which is usually seen
2) adjacent to the cystic artery during cholecystectomy, and
3) thence to the retroduodenal lymph nodes.

Some lymphatic channels from the fundus drain to the lymphatic channels in the liver capsule

Front 28

Motor and sensory sympathetic nerves

Back 28

1) from the coeliac plexus reach the gallbladder along the hepatic artery, and the

parasympathetic motor supply comes from the right and left vagus nerves.

Front 29

I) The bile ducts

Back 29

, the common hepatic duct runs for some 2.5 to 3.5 cm down to its confluence with the cystic duct, resulting in the formation of the common bile duct
In 5 per cent of people the cystic duct spirals behind the common hepatic duct and enters the bile duct low down within the pancreas

Front 30

In............. per cent the cystic duct opens directly into the confluence of the bile ducts

Back 30

2

Front 31

The common bile duct is normally................cm in length and about .............. mm in diameter in anatomical specimens

Back 31

10 to 12
6

Front 32

upper limit of normal measured by ultrasonography is ................. mm, whilst on direct cholangiography, when the duct is deliberately distended, it may be ...................mm in diameter

Back 32

7
10

Front 33

The common hepatic and bile ducts are supplied by adjacent arteries that supply two axial arteries that run at________________o'clock along the bile duct wal

Back 33

3 o'clock and 9